Method for converting a structure into a disinfestation apparatus

ABSTRACT

A disinfestation apparatus that treats an existing structure with heat and is designed to be portable is disclosed.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims the benefit under any applicable U.S. statute to U.S. Provisional Patent Application No. 60/291,407 filed May 16, 2001, titled PORTABLE HEAT-TREATING DISINFESTATION APPARATUS.

FIELD OF THE INVENTION

The present invention relates generally to an apparatus for eradicating pests in commodities, wood products, paper products, machinery, appliances that dispense foods or drinks and packaging materials and, in particular, a portable apparatus for eradicating pests using heat.

BACKGROUND OF THE INVENTION

Modern transportation means have made it feasible to transport foods, machinery and other commodities from one geographical region to markets in regions on the other side of the world. In addition, equipment that holds foods or drinks, such as vending machines, water-coolers, coffee machines, etc., have a high incident of infestation by cockroaches, other pests and larvae and their eggs. This infestation can be present in any imported, exported or domestic consignment due to the heat, moisture and dark cavities in their design.

Wood packing such as pallets, dunnage, crating, packing blocks, drums, cases, load boards, pallet collars, commodities, related and un-related machinery and skids can be present in any imported, exported, or domestic consignment, including consignments which would not normally be the target of phytosanitary inspection. Wood packing is frequently made of non-manufactured, low quality inexpensive raw coniferous and/or non-coniferous wood that may not have undergone sufficient processing time or treatment to remove or kill pests present within raw wood and therefore becomes a pathway for the introduction and spread of pests. Furthermore, wood packing is very often re-used (in that packing received with an imported consignment may be used again to accompany a second consignment). Therefore, the true origin of any piece of wood packing material is difficult to determine and thus its phytosanitary status cannot be ascertained or guaranteed.

In all regions of the world, imports of automobiles, machinery, parts and other non-food products are fumigated with Methyl Bromide or Ethylene Dibromide to kill pests hiding within various machinery or packaging. However, these chemicals can damage the ozone layer, and the residue left behind by these chemicals is harmful to people.

Heat treatment is an effective method for controlling pests without the drawbacks of fumigation e.g., highly toxic chemicals, airtight fumigation containment, certified pest controller(s), regulation by various state and/or federal agencies, and lengthy treatment/clearing times. Studies have documented that temperatures at or above 120 degrees Fahrenheit for thirty minutes is lethal to insects and pests. (Forbes and Ebling 1987, Sheppard 1984, Quarles 1995, and Zeichner 1998) The NPPO (National Plant Protection Organization) has established requirements for non-manufactured wood packing to manage the pest risk associated with this pathway. The process for establishing import/export requirements for wood packing may be different from that used for commodities moving as consignments. The normal process of undertaking risk analysis to determine if measures are necessary and the strength of such measures are frequently not possible for wood packing material because its origin and phytosanitary status may not be known. For this reason, it has become mandatory to regulate wood packing broadly by applying globally accepted measures that eliminate any presence of the more important regulated pests and significantly reduce the risk for a number of others.

SUMMARY OF THE INVENTION

Recent laws passed in Canada and in the European Union require that all wood and wood products and packing materials entering their respective countries be treated so as to eradicate pests. This invention embodies a proven treatment method which requires that wood packing be subjected to an elevated temperature (i.e., at least 56° Celsius) for an extended period of time (e.g., at least thirty minutes).

Vending machines, water coolers, coffee machines and similar equipment lend themselves to be treated effectively with heat to eliminate pests without damaging the equipment. With the use of heat, no risk of chemical transfer to water or vending products can occur, thus greatly reducing liability. Moreover, there is a commercial need for a portable heat disinfestation apparatus that can eradicate pests and be moved from one location to another. The present invention describes a portable device that eradicates pests by the use of heat and that is relatively quick and easy to manufacture.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and, together with the description, serve to explain the principles of the invention.

In the drawings:

FIG. 1A is a side plan view of a portable heat-treating disinfestation apparatus according to the present invention using a remote direct fired heating system;

FIG. 1B is a side plan view of a portable heat-treating disinfestations apparatus utilizing a trailer that can be moved by a tractor unit using a remote direct fired heating system;

FIG. 2 is a top view of the portable heat-treating disinfestation apparatus illustrated in FIG. 1 with the direct fired heating system attached to the rear of the apparatus;

FIG. 3 is a rear view of the portable heat-treating disinfestation apparatus illustrated in FIG. 2;

FIG. 4A is a front interior view in one embodiment of the portable heat-treating disinfestation apparatus illustrated in FIG. 1 (used with a direct fired, electric, or indirect fired heater) with the doors opened;

FIG. 4B is a front view of the portable heat-treating disinfestation apparatus illustrated in FIG. 1 with the doors closed;

FIG. 5A is a portable heat-treating disinfestation apparatus according to the present invention using an indirect fired system;

FIG. 5B is a side view of the apparatus illustrated in FIG. 5A with a set of trailer wheels attached;

FIG. 5C is a side view of another embodiment of the apparatus illustrated in FIG. 1B using a remote indirect fired heating system connected to the apparatus with either rigid duct, flexible duct, or a combination of both;

FIG. 6A is an enlarged side view of a typical direct fired heating system capable of being used with the portable heat-treating disinfestation apparatus illustrated in FIGS. 1A, 1B, 2, and 3;

FIG. 6B is an enlarged end view of the inlet end of the direct fired heating system illustrated in FIG. 6A;

FIG. 7 is a side plan view of a portable heat treating disinfestation apparatus according to the present invention using an indirect fired heating system;

FIG. 8 is a cross-sectional view of the plenum shown in FIG. 7;

FIG. 9A is a top view of the hypotenuse side that forms the ducts of FIG. 7;

FIG. 9B is a side view of the duct portion illustrated in FIG. 9A;

FIG. 10 is a front view of an end cap for a duct used in the embodiment of FIG. 7;

FIG. 11 is an enlarged cross-sectional view of a longitudinal side wall of the chamber;

FIG. 12 is a top cross-sectional view of the embodiment illustrated in FIG. 7;

FIG. 13A is an enlarged front view of the return air baffle of FIG. 7;

FIG. 13B is an enlarged side view of the return air baffle of FIG. 7;

FIG. 14A is an enlarged end view of a T-shaped floor section of FIG. 14B;

FIG. 14B is a front interior view of the portable heat-treating disinfestation apparatus illustrated in FIG. 7 (used with an indirect fired heater) with the doors opened; and

FIG. 15 is a side view of a direct fired heating system that becomes an integrated component of the portable heat-treating disinfestation apparatus of FIGS. 1A, 1B, or 5C with either rigid duct, flexible duct, or a combination of both.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

For the purpose of this patent, the term “pest” shall be defined as, but not limited to, any unwanted living organism susceptible to eradication by means of heat (e.g., insects, biological organism, mold, fungus, anthrax, etc.)

For the purpose of this patent, the term “heater” shall be defined as, but not limited to, any device that has the means to raise/increase the temperature of air or a given substance either directly or indirectly, through conduction, convection, or radiation. The source of heat can be derived from the means of a combustible fossil fuel (e.g., propane, natural gas, heating oil, etc.) electricity, steam, coal, or wood.

For the purpose of this patent, the term “products” shall be defined as, but not limited to, non-manufactured wood packing (e.g., pallets, dunnage, crating, packing blocks, cases, load boards, skids, etc.), paper products, appliances that hold and dispense foods or drinks (e.g. vending machines, water coolers, coffee machines), and machinery equipment, and commodities.

In describing a preferred embodiment of the invention, specific terminology will be selected for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents that operate in a similar manner to accomplish a similar purpose.

Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings in which a portable disinfestation apparatus utilizing heat, in accordance with the present invention, is generally indicated at 10.

Referring to FIG. 1A, a chamber 12 that is designed to be movable is set in place. The chamber 12 is preferably insulated in order to conserve energy in bringing the interior of the chamber up to a desired temperature and in maintaining that temperature but may not be insulated in some cases due to use of existing truck body or the like. The chamber 12 may either be of new construction or refurbished (e.g., a former reefer container, an insulated trailer on wheels, etc.).

The interior of the chamber 12 may be designed to hold specific goods or commodities. For example, the width of the chamber 12 may accommodate a standard pallet, and/or shelves may depend from the walls to hold certain shipping containers.

In a preferred embodiment, the floor of the container may be reinforced to allow a forklift to ingress and egress. This feature will greatly facilitate loading and unloading of the chamber 12.

The chamber 12 preferably has a rectangular shape. This allows the chamber to be shipped conveniently on a flatbed truck, train car, ship or other means of transportation.

Referring to FIGS. 1A, 2, 3, 4A and 5A, the chamber 12 has a flat bottom 14, opposing parallel first and second endwalls 16 and 18 depending upward along the traverse side of the flat bottom 14, and opposing parallel third and fourth endwalls 20, 22 depending upward along the longitudinal sides of the bottom 14. A top 24 encloses the structure. A door or a pair of doors 42, 44, are located in the first endwall 16 to provide a means of ingress and egress to the interior of the chamber 12.

An important feature of the present invention is its portability. Forklift pockets may be formed below the chamber 12 to allow a fork-lift to raise the chamber in order to move or reposition the apparatus 10. In an alternative embodiment, lifting mounts may be produced in the upper four corners of the chamber 12. The lifting mounts provide a means for an overhead crane, large fork-lift machine or ship's crane to attach to the chamber 12 in order to lift the chamber.

Other preferred embodiments are illustrated in FIGS. 1B, 5B, 5C and 7. As shown in FIG. 5B, a plurality of wheels 99 can be attached to the underside of said chamber 12. (Alternatively, the chamber 12 can be attached to a flatbed trailer or other platform that has wheels 99.) Attached closer to the end of the chamber 12 opposite the wheels is a stand 92 and a means 97 for pulling the chamber 12. The stand allows the apparatus 10 to sit without external assistance.

As illustrated in FIGS. 1B, 5B, and 5C the chamber 12 may be adapted so that it can be easily mounted on, and removed from, a trailer bed 95. The trailer bed 95 has a plurality of wheels 99 at its back end. At the front end of the trailer bed 95 are a means 97 to allow the trailer/chamber to be pulled by a truck (i.e., a tractor-trailer vehicle) and a stand 92.

Referring to FIGS. 3 and 4A, the rear wall 16 of the chamber has an inlet 28 and an outlet 29. An inlet duct 40, connects the inlet 28 to a direct fired heater 30. The outlet 29 is open to the ambient air.

In one embodiment a pair of doors 42, 44 pivot about hinges that are connected to side walls 20, 22, respectively, as illustrated in FIG. 4B. The doors 42, 44 swing independently of each other and allow ingress and egress to the interior of the chamber 12.

Referring now to FIGS. 6A and 6B, a typical direct fired heating unit 30 is illustrated. This type of heating unit is usually identified by its elongated cylindrical housing 32; however, some direct fired heaters have a rectangular or other polygonal shaped housing. A fan or blower connected to an electric motor and a burner assembly are mounted within the housing 32. The fan or blower draws air in from the inlet end 34 of the heater 30, pushes the air through the housing and over the burner assembly and out the outlet end 36 of the housing.

In one embodiment the burner assembly is designed to mix oxygen from the air passing by with natural or propane gas. After an igniter ignites the air/gas mixture, the burner assembly ensures a controlled burn as long as gas is delivered to the burner assembly from an external source. Approximately the entire second half of the housing 32 acts as a combustion chamber. As the air passes through the flame at the burner assembly and through the combustion chamber, it is heated to a desired temperature.

A control box 38 is mounted on the exterior of the housing 32. The control box 38 protects electronic circuitry used to control the operation of the heater 30. Specifically, the electronic circuitry controls the amount of gas delivered to the burner assembly, provides power to the electric fan motor and the starts the igniter.

As illustrated in FIG. 3, the heater 30 is mounted on the outside of the rear wall 16 of the chamber 12. Referring now to FIGS. 6A and 6B, first and second brackets 84, 85, respectively, are used to secure the direct fired heater 30 to the chamber's end wall 16.

Referring again to FIGS. 1A, 1B, 3, 6A and 6B an input air duct 40, connects the outlet 36 of the direct fired heater 30 to an inlet 28 in the chamber. In FIG. 3, the outlet 29 of the chamber 12 is located proximate the inlet 34 of the heater 30. This allows the heater to simultaneously draw in fresh air along with some of the relatively hot air being expelled from the interior of the chamber 12. This method saves energy while ensuring that the air inside of the chamber 12 stays at the desired temperature.

Referring now to FIG. 5C, a portable apparatus 10 utilizes a remote indirect fired heater 32 as illustrated. An input air duct 40, connects the outlet of the indirect fired heater to the inlet 28 of the chamber 12. The outlet 29 of the chamber is connected to the inlet of the indirect fired heater 32 through return air duct 41. This allows the heater to continuously re-circulate the heated air within the chamber thus saving energy and ensuring the air inside the chamber 12 stays at the desired temperature.

Referring now to FIGS. 5A, 5B and 7, a portable disinfestation apparatus 10 utilizing an indirect fired heater 50 is illustrated. The two types of disinfestation apparatus are basically the same except that the air in an indirect fired heat system does not come in direct contact with a burning flame. An indirect fired heater 50 is similar to gas-burning heaters found in many commercial buildings.

In one embodiment illustrated in FIGS. 7 and 14B the indirect fired heater 50 has its output mounted directly over the plenum inlet 60 of the chamber 12. Ductwork 52 connects the outlet 61 of the chamber 12 to the inlet of the indirect fired heater 50. (It should be noted that FIG. 4A shows the plenum inlet 28 as circular in shape; however, because the general shape and design of the indirect fired heater 50 is different than a direct fired heater 30, the plenum inlet 60 is usually rectangular when used with an indirect fired heater 50.

The interior of the chamber will now be described. Although the drawings show an indirect fired heating system 50 in connection with the interior details, it would be understood by one skilled in the art that the interior chamber of an apparatus 10 using a direct fired system 30 is substantially identical.

A side cut away of the chamber 12 is also illustrated in FIG. 7. A plenum 55 is formed on the inside of the back wall 16. The plenum 55 is substantially rectangular in shape and covers the entire width (i.e., from longitudinal wall 20 to longitudinal wall 22). A portion of the ceiling of the chamber forms the top of the plenum 55. A plenum deck 56 forms the bottom.

Two diametrically opposed ducts 51, 53 assembled from a pre-determined number of duct sections extend from the plenum 55 substantially the entire length of the chamber 12. The ducts 51, 53 have a triangular cross-section as shown in FIG. 14B. A portion of the ceiling of the chamber forms the top of each duct 51, 53 and a portion of the sidewall of the chamber forms the side of the duct.

Referring now to FIG. 8, the face 62 of the plenum 55 is illustrated. FIG. 9A is a top view of the hypotenuse or long side 64 of a triangular duct section. As illustrated, a plurality of mounting holes 66 is positioned along each edge of the hypotenuse side of the duct section. FIG. 9B is a side view of the hypotenuse side 64 6f the duct section.

The bottom portions of the hypotenuse side 64 are attached to the side wall (e.g., preferably with screws, but rivets, spot welding or other means may be used) of the chamber 12, while the top portion is attached in to the ceiling of the chamber 12. The hypotenuse side 64 of the duct sections are joined to the upper left and upper right corners of the plenum face 62. An end cap 71 seals off the end of each duct.

Duct end caps 71, as shown in FIG. 10, close off the ends of each duct 51, 53. The end caps 71 abut against the hypotenuse side 64 and are secured by screws through mounting holes 69 to the ceiling and wall of the chamber 12.

The ducts 51, 53 serve to distribute the warm air away from the plenum 55 to be evenly distributed to the interior of the chamber 12.

In a preferred embodiment, the walls of the chamber are chamfered to form a plurality of parallel, vertically-oriented channels 77 that extend from the ceiling to the floor of the chamber 12. The channels 77, best illustrated in the partial cross-sectional wall view of FIG. 11, help to ensure that the warm air does not stay suspended above the products placed inside the chamber. The channels 77 provide a vertical passageway for the air to circulate within the chamber 12.

FIG. 14A is an enlarged view of a floor portion. As illustrated, this system can utilize external rigid or flexible ducting as means of transport for heated supply air or return air, the floor is comprised of a plurality of T-shaped supports 78 that extend upwards from a base 79. Referring again to FIG. 14A, the T-shaped supports 78 define a plurality of channels 88 on the floor of the chamber. The channels 88 provide a horizontal floor-level passage for the air to move within the chamber 12. The T-shaped supports 78 are made of metal in one embodiment so that they may support the weight of a fork lift or other machinery needed to load product within the chamber.

Referring now to FIGS. 13A and 13B, a return baffle 70 depends from the deck of the plenum. Referring again to FIG. 7, the return baffle 70 ensures that only the cooler air near the floor of the chamber is returned to the heater 50.

In practice, the products are placed within the chamber 12. The doors 40, 42 are closed. The heater 50 ignites and the motor in the heater begins to turn the fan. Air is drawn out of the chamber 12 through the outlet 61 and into the heater 50. The air is heated to a set temperature and is blown through plenum inlet 60 into the plenum 55. Within plenum 55, the heated air is divided substantially in two and directed into the ducts.

The ducts 51, 53 distribute the heated air along the entire longitudinal dimension of the chamber 12. The gutters 77 direct the heated air downward along the walls of chamber 12. Since hot air rises, some of the air directed by the gutters 77 moves to the center of the chamber 12. As the heated air cools, it falls to the floor of the chamber 12. The T-shaped supports 78 provide channels 88 so that the cooled air can be returned, unobstructed to the return baffle 70 where it will eventually be drawn back through the outlet 61 and into the heater 50.

Although this invention has been described and illustrated by reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made which clearly fall within the scope of this invention. The present invention is intended to be protected broadly within the spirit and scope of the appended claims. 

1-12. (canceled)
 13. A process for converting an existing enclosed structure into an apparatus for eradicating pests, the enclosed structure having a first endwall, a second endwall, a left wall, a right wall, a ceiling and a floor that define an interior chamber, the process comprising the steps of: providing a heater capable of heating the interior air of the chamber to a desired temperature for a desired period of time, the heater having an inlet for drawing in cooler air and an outlet for outputting air after it has been heated, said heater being located outside of said structure; modifying the first endwall with a chamber inlet for accepting heated air from the heater; attaching a plenum on the inside of said chamber proximate the chamber inlet, the plenum being designed to accept and assist in distributing the heated air; hanging ductwork on the inside of said structure proximate the ceiling, the ductwork communicating with said plenum for allowing heated air to travel from the plenum through the ductwork, said ductwork having a plurality of perforations for distributing the heated air from the ductwork throughout the chamber; and attaching a return baffle proximate the plenum, said return baffle communicating with said plenum for drawing in at least a portion of the air in the chamber and directing said drawn air back into the plenum preferably to be remixed with the heated air.
 14. The process of claim 13 further comprising the step of insulating said walls, the ceiling and the floor.
 15. The process of claim 13 wherein said heater is a direct fired heater that draws air into its inlet from outside the chamber.
 16. The process of claim 13 wherein said heater is an indirect fired heater, further comprising the steps of: providing a plenum deck between the plenum and the return baffle for at least partially restricting the air drawn from the chamber from being directed to the plenum; modifying the endwall proximate the return baffle with a chamber outlet; and connecting the heater inlet to the chamber outlet with a duct for directing at least a portion of the air drawn by the return baffle from the chamber into the heater.
 17. The process of claim 16 wherein said ductwork comprises two elongated ducts extending from the plenum along the entire length of the structure, one elongated duct positioned along the left wall and the other elongated duct positioned along the right wall.
 18. The process of claim 16 wherein said ductwork comprises a left side elongated duct and a right side elongated duct, the elongated ducts having a triangular cross-section wherein a portion of the ceiling and a portion of the left wall form two sides of the left side elongated duct and a portion of the ceiling and a portion of the right wall form two sides of the right side elongated duct.
 19. The process of claim 18 further comprising the step of providing a fan assembly that communicates with said plenum for forcibly blowing air into the ductwork. 